Abstract:
Lukas Novotny and colleagues at the University of Rochester, USA, have taken inspiration from radio wave manipulation and designed an optical antenna that can boost the interaction between light and the particle being studied. The fluorescence of a single molecule can be enhanced by more than a factor of 10 using this technique. The optical antenna, which consists of a single colloidal gold nanoparticle on the end of a pointed dielectric fibre, replaces a conventional focusing lens or objective, so the incoming light can be focused to dimensions smaller than the diffraction limit.